Tumbler lock



Sept. 5, 1967- H. GREENWALD 3,339,384

Y TUMBLER LOCK 'Filed July 6, 1965 2 Sheets-Sheet l INVENTOR HarryGreenwald ATTORNEY Sept. 5, 1967 H. GREENWALD 3,339,334

TUMBLERLOCK Filed July 6, 1965 2 Sheets-Sheet 2 FIG. l2 FIG. 1 1

INVENTOR. Harry Greenwald ATTORNEY United States Patent tifice 3,339,384TUMBLER LOCK Harry Greenwald, Whitestone, N .Y., assignor of onethrdeach to Louis Wolff and Harry Silberglait, Brooklyn, N.Y.v

Filed July 6, 1965, Ser. No. 469,601 12 Claims. (Cl. 70-363) ABSTRACT FTHE DISCLOSURE This invention is directed to a tumbler lock and acomplementary key means constructed so as to insure the key means firstsetting the code pins of the tumbler lock to permit alignment of thecode pins so as to render the lock members rotatable with respect to oneanother before the driving connection is established between the keymeans and one of the movable lock members. Thel invention furthercontemplates a lock pin construction for such tumbler locks whereby suchpins can be retained within their respective bores in the event the lockis disassembled for any reason. Also the lock pins are constructed withmeans to limit axial movement thereof so as to prohibit overstressing ofthe springs acting thereon when efforts are made to pick such locks.

This invention relates in general to a tumbler type lock or the like,and more specifically to a tumbler type lock adapted for use on vendingor coin operated machines that is particularly constructed and arrangedto render the lock theft proof.

Heretofore tumbler locks of the type to which this invention relateswere constructed so as to render them vulnerable to picking.Consequently, operators of coin operated machines and vending machinessecured by the prior known lock constructions have suffered aconsiderable amount of loss due to the skill which certain unscrupulouspersons have developed in picking the locks of the prior knownconstructions. It has been discovered that the unscrupulous lock pickersare successful in picking the locks previously used on vending machinesor the like because they have been able to apply a torque on the rotarycomponent of the lock prior to the setting up of the code pins whichmust be set to render the lock operative. By so doing, the lock pickercould individually set the respective code pins and thus successfullyopen the lock. Because the key of the prior construction was engaged indriving position before the code pins are set, the pickers by applying arotary driving force on the rotary member of the lock With a toolsimulating a key could effect limited rotary movement of the rotarymember of the lock due to the Working tolerances of the tumbler pins andtheir respective bores an amount sufficient to permit the picker to setone or more of the code pins. By successfully performing the operation anumber of times, the picker could eventually set each of the code pinsso that the lock was finally rendered operative. As a result,unscrupulous pickers have developed a considerable amount of skill -inpicking lsuch lock solely because such locks were constructed in amanner which permitted the key to engage in driving relationship withthe rotary member of the lock before the code pins had been set.

Another disadvantage which has been noted in the tumbler locks of priorconstruction was in the picking of such locks, it was also necessary forthe picker to exert a considerable axial force to displace the pins, andin doing so would frequently overstress the springs. With the springmeans acting as tumbler pins stressed beyond the resilient limits, thelock was rendered unreliable in use, and would have to be eitherextensively repaired or replaced. Another eifort employed to gainunauthorized access to the 3,339,384 Patented Sept. 5, 1967 money box ofa coin operated or vending machine was to attempt to drill through thelock assembly. For this reason hardened plugs or key guides have beenutilized to deter such drilling. However, each such hardened key guidesmerely deterred and did not solve the problem of drilling through thelock.

l Another disadvantage noted in the tumbler locks of the type utilizedon vending and/ or coin operated machines was that extreme difficultyhad been encountered by an operator of such vending machines in changingthe coding of the lock. The reason for this was that the locks of knownconstruction did not utilize any positive means for retaining thetumbler pins Within the lock. Consequently, when such locks were takenapart to change the coding thereof, the pins would frequently pop outand become lost or misplaced.

It is, therefore, an object of this invention to overcome each of theforegoing noted disadvantages by providing a tumbler lock constructionthat is rendered theft proof.

It is another object of this invention to provide a tumbler lock inwhich the drive connection is not affected until after the code pinshave been set.

It is another object of this invention to provide a tumbler lockconstruction adapted for use on coin operated or vending machines inwhich the coding of the pin can be readily changed in the field.

It is another object of this invention to provide a tumbler lock inwhich the tumbler pins are positively retained in the lock so as toenhance the changing of the coding of the lock by a relatively unskilledperson in the field.

Another object of this invention is to provide means for limiting themovement of the tumbler pins so as to prohibt over stressing of thespring means acting thereon by a would be lock picker.

Another object of this invention is to provide a rotary type tumblerlock with freely rotatable key guide so as to prohibt drilling throughthe lock.

Still another object of this invention is to provide a lock constructionwhich can be manufactured and assembled with relative ease, and which issimple and positive in operation.

The foregoing objects, and other features and advantages are attained bya tumbler lock construction comprising a tubular housing, and a pair ofjuxtapositioned members disposed within the housing which are arrangedfor relative movement with respect to one another. Each of therespective members is provided with a plurality of axially aligned boresformed thereon. A set of lock pins are mounted in the bores of one ofthe said members, and a set of cooperating code pins are disposed withinthe bores of the other member. Cooperatively associated and operating onthe lock pins are means for normally biasing the respective lock pins sothat the en-d portions thereof extend into the aligned bores of theother member to prohibit relative movement therebetween in the lockposition of the lock.

In accordance with this invention a key means, for effecting axialdisplacement of the code pins to set the lock pins a correspondingamount to effect disengagement of the lock pins from the other member,is provided with means Ifor affecting the driving connection between thekey and the rotary member only after the code pins and locking pins havebeen set to effect relative rotation `of the lock members when the keyis turned.

Means are provided for positively retaining each of the lock pins Withintheir respective bores so that assembly of the lock and/or changing ofthe code pins can be facilitated. Also in one form of the invention ameans is provided for rotatably journalling the key guide of the lock soas to render the same freely rotatable in the assembled positionthereof. Means are provided in accordance with this invention forlimiting the axial displacement of the lock pins within their respectivebores so as to prohibit over stressing of the resilient or spring meansacting thereon.

A feature of this invention resides in a tumbler lock construction andkey therefor wherein cooperating drive means are provided on the key andthe lock to effect a driving connection ybetween the key and the lockonly after the code pins have been set by the key.

Another feature of this invention resides in means for positivelyretaining the lock pin within the bore of its associated lock member.

Another feature of this invention `resides in means for limiting theaxial displacement of the lock pins within their respective bores so asto prohibit over stressing of the spring means operating thereon.

Another feature of this invention resides in the -provision of a keyguide mounted for free rotational movement with respect to the key plugof the lock.

Another feature of this invention resides in the relative ease withwhich the coding of the lock construction can be changed at will.

Another feature of this invention resides in the provision of a tumblerlock construction specifically constructed and arranged to prohibitwould be pickers from unauthorized opening of the lock.

Other features and advantages will become more readily apparent whenconsidered in view of the drawin-gs and specification in which:

FIGURE l is a front end view of a tumbler lock construction embodyingthe instant invention.

FIGURE 2 is a cross-sectional view of the lock taken along line 2-2 onFIG. 1.

FIGURE 3 is a detail view of the plu-g member of FIG. 2 having portionsthereof shown in section.

FIGURE 4 is a left end View of the plug member of FIG. 3.

FIGURE 5 is a right end view of the plug member of FIG. 3.

FIGURE 6 is a detail sectional view of the pipe member incorporated inthe lock construction of FIG. 2.

FIGURE 7 is a left end view of the pipe member of FIG. 6.

FIGURE 8 is a cross-sectional view of the lock housing.

FIGURE 9 is a left end view of the lock housing of FIG. 8.

FIGURE 10 is a right end view of the lock housing of FIG. 8.

FIGURE 11 is a side elevation view of a. key construction adapted tooperate on the lock of FIGURE 2.

FIGURE 12 is a left end View .of the key of FIG- URE 11.

FIGURE 13 illustrates a cross-sectional View of a modified form of theinvention.

FIGURE 14 is a cross-sectional view of still another modified form ofthe invention.

Referring to the drawings, FIGURES 1 through 8 disclose a tumbler lockconstruction 20 of this invention adapted `for use on coin operated orvending machines. Such locks are employed to permit authorized accessonly to the coin box and/ or operating mechanism of such machines.

As shown, the tumbler lock 20 comprises of a tubular housing 21 having afront facing portion 22 terminating in an inturned flange 23 to definean angular front opening 24. Between the opened ends of the housing 21is a bore 25 -for housing the component parts of the lock as will behereafter described. The bore 25 terminates in an internal annularshoulder 26 that is spaced inwardly from the inturned fiange 23 or frontopening 24 of the housing 21. Disposed within the bore 25 of the housingis a plug member 27. The plug member 27 is provided with a head endportion 28 and a connected stem portion 29 of reduced cross-section. Asshown, the head end portion 28 is provided with an outer periphery whichis sized to be received within the bore 25 of the housing with the frontface of the head end portion 28 disposed in abutting relationship withthe internal shoulder 26 of the housing. The arrangement is such thatthe plug member 27 is rendered free to rotate Within the bore 25 of thehousing. Connected to the head end portion 28 of the plug 27 is a keyguide 30.

As shown in FIGURE 2, the enlarged end portion 30A of the key guide 30is provided with a circumference which is spaced from the circumferencedefined by the flange 23 forming the front opening of the housing.Accordingly, an angular space 31 is defined between the exteriorcircumference of the key guide 30 and the inner circumference of theinturned flange 23 to define a key opening for receiving the cylindricalshank 32 of a key 33 illustrated in FIGURES 11 and 12. The shank 34 ofthe key guide 30 is force fitted into a bore 35 formed in the plugmember 27.

The inturned fiange 23 defining the front opening of the housing isprovided with a notched portion to define a key way 36. Accordingly, asit will be hereinafter described, the key way provides the means adaptedto align with a lug 37 formed on the key 33 for orientating thecylindrical shank 32 of the key 33 with respect to the lock to effectthe actuation thereof.

An annular pipe member 38 is mounted on the stern portion 29 of the plug27 within the tubular housing 21. The arrangement is such that the frontfacing of the annular pipe member 38 is disposed contiguous to the headend portion 28 of the plug 27. The annular Pipe member 38, in turn isfixed against relative rotation with respect to the housing 21 by meansof a set screw 39 which is threaded through a tapped opening extendingthrough the Wall portion of the housing 21.

In accordance with this invention the annular pipe member 38 is providedwith a plurality of circumferentially spaced bores 40 extendinglongitudinally therethrough. A washer 41 positioned on the stem 29 ofthe plug member 27 is disposed contiguous the rear facing of the pipemem-ber 38 to form a base or bottom for the bores 40 extending throughthe pipe member. A retainer ring 42 secures the annular pipe member 38and associated washer 41 in position on the stem 29 of the plug member27. The extended end portion 29A of the stern 29 may be threaded forreceiving a suitable lock washer or lock nut (not shown) by which thelock is secured to the cooperating mechanism of the vending machinewhich is also not shown.

Referring more particularly to FIGURES 2, 3 4, and 5 the head endportion 28 of the plug member 27 is also provided with a plurality oflongitudinally extending bores 43. As shown a pair of opposed bores44-45 are counterbored for receiving a drive pin 46 which has an endportion extending forwardly of the head end portion 28 of the plug. Theother bores 43 formed in the head end portions are axial aligned withthe bores 40 of the annular pipe member 38 in the lock position of thelock.

In accordance with this invention, a lock pin 47 is disposed in each ofthe bores 40 in the pipe member 38. A means is provided for affectingpositive retention of the lock pins 47 within each of its respectivebores 40.

As best seen in FIGURE 2 positive retention of the lock pins 47 in thebores 40` is accomplished by providing the bore 40 with an internalshoulder 40A as by counterboring, and by providing the pins 47 with acomplementary flange 47A adapted to abut against the shoulder 40A soformed. Inter-posed between t-he shoulder end 47A of the pin 47 and thewasher 41 closing the rear end of the respective bores 40 is a resilientspring means 48 for normally biasing the pins 47. In the illustratedform of the invention the spring means 48 comprises a coil spring whichis utilized to normally urge or project the lock pins 47 into thealigned bores 43 of the head end portion in the locked position of thelock. Accordingly, the ends of the respective pins 47 projecting throughthe bore 40 of the pipe member and into the aligned bore 43 of the headend member 28 serves to prohibit relative rotation between the plugmember 27 and the annular pipe member 38.

Disposed within each of the aligned bores 43 of the head end portion 28is a code pin 49. It will be understood that the code pins 49 are ofdifferent lengths. The arrangement being such that each of the code pins49 is required to be set or axially displaced a predetermined amount sothat each of the cooperating lock pins 47 are axially displaced acorresponding amount, when properly set, the adjacent abutting endportions of the respective cooperating lock pins 47 and code pins 49 aredisposed in alignment with the respective contiguous face portions ofthe Ihead end portion 28 of the plug 27 member and the annular pipemember 38. Accordingly, rotation of the plug member 27 relative to thepipe member can be affected upon the turning of the key when theabutting ends of the pins 47, 49 align with the contiguous faces ofmembers 28 and 38.

Referring to FIGURES 11 and l2 t-here is shown therein the keyconstruction 33 adapted to be utilized to operate on the lock describedwith respect to FIGURE 2. As shown, the key comprises a tubular stemportion 32 which is adapted to be inserted into the annular spacing 31defined between the key guide 30 and the inturned flange 23 of t-hefront facing. Projecting radially adjacent the tip end o'f the tubularkey stem 32 is a lug 37 which is adapted to 4be received in a key Way 36defined in the front facing of the lock housing 21 to properly align ororientate the key 33 with respect to the code pins 49 of the lock.

Circurnferentially spaced :about the outer circumference of the tubularshank 32 of the key are a plurality of notched portions 60 to define aseat to accommodate the respective extended end portions of the c-odepins 49. As best seen in FIGURE l1 the axial length of the respectivenotch or seats 60 formed about the outer circumference of the key varyin accordance with the respective code pins, the relative lengths of thekey seats 60 being determined -by the respective lengths of the codepins adapted to be received therein.

The oppositely opposed recess or seats indicated at 61 and 62 areprovided to make engagement or connection with the drive pins 46projecting forwardly of bores 44, 45 of the plug member 27. Accordingly,it is to be noted that the engagement of the drive pin notches or seats61,

62 on the key with the drive pins 46 of the plug member is not affecteduntil the respective code pin seats 60 have made engagement with therespective code pins 49 and have displaced them accordingly. Thus theturning torque which the key 33 applies to the head end member 28 uponturning thereof cannot lbe effected until each of the respective codepins 49 has been set to an unlocking position. With the constructiondescribed it will be apparent that a would be picker cannot impart atorque or rotative force on the head end 28 of the plug 27 beforesetting of the code pins 49. Consequently, the lock picking techniquesheretofore applied on the locks of prior constructions cannot beutilized on the lock construction herein described. This is because thelock herein described is constructed and arranged to render void thetechnique heretofore employed in picking locks of the type to which theinstant invention relates.

Means are lalso provided for prohibiting the over stressing of thespring members 48 acting on the lockv pin 47 in the event an excessiveforce applied to the lock pins as in an attempt to pick the lock. Thesemeans comprise of a limit pin 64 which extends rearwardly of therespective lock pin 47. Accordingly, it will be noted that when anexcessive axial force applied to the code pins 49 which in turn isimparted to the lock pin 47, the force will be Vlimited or-resisted bythe engagement lof the limit pin 64 against the washer 41 closing theends of the bores 40. Thus, the limit pin 64 functions to positivelylimit the displacement of the lock pin 47 within its respective -bore 40e and consequently limit the compression applied on the spring 48.

FIGUREv 13 is a modified form of the invention. FIGURE 13 disloses alock 70 which is similar in all respects to the construction describedwith reference to FIGURES l through 8 with the exception that the meansfor effecting positive retention of the lock pins 71 within theirrespective bores 72 has been modified. In this form of the invention itis to be noted that the lock pins 71 are provided with a diameter whichis slightly greater than that of the respective code pins 73 cooperatingtherewith. Accordingly, the bores 74 in the head end portion 75 Iof theplug member 76 accommodating the code pin are counter bored at one endto define a seat 77 for receiving the projected end of the enlargeddiameter lock pins 71. Accordingly, the head end portion 75 of the plugmember 76 functions to retain the lock pin 71 in their respective bores72.

Consequently, whenever it is desired to effect a change in the coding ofthe lock to either of the locks described with respect to FIGURES 2 or13, an operator in the field merely has to remove the internal Workingparts i.e. the plug and pipe member of the lock from the housing bydisengaging the set screw 39. The plug 27, 76; the pipe secured Ion thestem of the plug, and the key guide can then be readily removed throughthe back end of the housing 21. Accordingly, the code pins may bereadily removed, and in doing so the lock pinsare positively retained inposition within their respective bores as is apparent from theconstruction of either FIGURES 2 or 13. Accordingly, the respective codepins may be rearranged and/or replaced with varying sized code pins toalter a particular combination of -the lock. However, With every changein the combination of a lock, it will be apparent that a new key willhave to be constructed to accommodate the change of the code pins.Accordingly, with the coding of the lock so changed, the workingportions of the lock are again returned to position within the housing,and the housing secured in place by locking of the set screw.Accordingly, the lock is ready for use with a new combination.

FIGURE 14 illustrates still another modified form of lock in accordancewith lthis invention. In this form of the invention the key guide 81 isarranged so as to be freely rotatable with respect to the head endportion 82 of the plug member 8-3, to which it is secured. This isattained by providing the stem portion 84 of the key guide 81 with anannular groove 85. The head end portion 82 of the plug member 83 isprovided with a central bore 86 to receive the stem portion 84 of thekey guide 81. The dimensions of the stem 84 is such that the key guide81 is rendered freely rotatable with respect to the head end portion 82of the plug member 8-3. Means in the form of retaining pins 87 areutilized for rotatably journaling the key guide 81 within the bore 86 ofthe plug member 83. As shown, the head end portion 82 of the plug member83 is provided with a pair of opposed -radially extending bores 88arranged lto be disposed in alignment with the annular groove formed inthe stem 8-4 of the key guide in the assembled position thereof.

.Accordingly, the retaining pin 87 disposed within the radial bore 88are arranged so that -the inner ends thereof extend into the annulargroove 85 of the guide key. Thus, t-he retaining pins 88 in theassembled position of the lock function to positively retain the keyguide 81 to the plug member 83 so that the guide 81 is rendered freelyrotatable with respect to the head end portion of the plug 83.

With the key guide 81 rendered freely rotatable with respect to the headend portion 82 of member 83 of the lock; attempts to drill through thelock by placing a ldrill bit against the end of the key guide isrendered ineffective as the key guide 81 would rotate with the drillbit. Thus, drilling of the key guide 81 is prohibited thereby.

With respect to the embodiments shown in FIGURES 2 and 13, it will benoted that the key guide may be made of either a hardened steel orsofter material as may be desired by a particular vending machineoperator. In other respects, the operation of the lock as disclosed inthe embodiments of FIGURES 13 and 14 is similar to that described Withrespect to FIGURE 2.

While the instant invention has been described and illustrated withrespect to several embodiments thereof, it will be readily understoodand appreciated that variations and modifications may lbe made withoutdeparting from the spirit or scope of this invention.

What is claimed is:

1. A tumbler lock comprising:

a housing,

a pair yof juxtapositioned relatively movable members disposed withinsaid housing,

each of said members having a plurality of axially aligned bores formedtherein,

lock pins mounted in the bore of one of said members,

means for normally biasing said lock pins so that the ends of saidrespective lock pins extend into the aligned bores of said other memberto prohibit relative movement therebetween,

code pins disposed in the bore of said other member,

a key guide,

means for connecting said key guide for free relative rotation withrespect to said other member,

and a key means for effecting axial displacement of said code pins andlock pins a proportional amount to disengage said lock pins from saidother member,

and complementary means on said key means and said other member foreffecting a driving connection between said key means and said othermember whereby said driving connection is engaged only after said codepins have been displaced a proportional amount necessary to permitrelative movement between said members.

2. The invention as defined in claim 1 wherein each of said lock pinsinclude means for limiting the axial displacement thereof within theirrespective bores.

3. A tumbler lock comprising:

(a) a housing,

(b) a pair of juxtaposition members disposed within said housing forrelative rotational movement with respect to one another,

(c) each of said members having a plurality of axially aligned boresformed therein,

(d) lock pins mounted in the bore of one of said members,

(e) means normally biasing said l-ock pins so that the ends of said lockpins extend into the aligned bores of said other member to prohibitrelative movement therebetween,

(f) means for positively retaining each of said lock pins in itsrespective bore,

(g) a code pin disposed in each of the bores of said other memberwhereby said code pins are in contiguous relationship with the ends ofsaid lock pins for effecting axial displacement of said lock pins, a keyguide, and means for connecting said key guide for free relativerotation with respect to said other member to deter the drilling of saidlock,

(h) and a key means for effecting axial displacement of said code pinsand lock pins a proportional amount to disengage said lock pins fromsaid other member,

(i) and, complementary means on said key means and said other member foreffecting a driving connection between said key means and said othermember whereby said driving connection is engaged only after said codepins have been displaced the proportional amount necessary to permitrelative rotational movement between said members.

4. The invention as defined in claim 3 wherein said latter means foreffecting the drive includes:

(a) a drive pin projecting forwardly of said other member,

(b) and, means formed lon said key for engaging with said drive pin onlyafter said code pins have been displaced to permit relative movementbetween said members whereby the torque of turning said key meansimparts a rotary movement to said other member.

5. A lock construction comprising:

(a) a plug member having a plurality of bores extending axiallytherethrough,

(b) a Ipipe member mounted contiguous to said plug member,

(c) said pipe member having a plurality of bores formed therein, saidbores being disposed in axial alignment with the bores of said plugmember,

(d) a lock pin located in each bore of said pipe member,

(e) spring means normally biasing each of said lock pins so that theends of said lock pins normally extend into the aligned bore in saidplug member to normally prohibit relative rotation between said plug andpipe members,

(f) a code pin disposed in each bore of said plug member,

(g) said code pins being of varying lengths,

(h) a key guide connected to said plug member,

(i) a lock housing encasing said pipe and plug members,

(j) said housing defining with said key guide an annular key opening,

(k) a key way formed in said housing,

(l) a drive means connected to said plug member,

(m) key means for operating said lock when inserted into said keyopening,

(n) said key means including a complementary driving means to engage thedrive means of said plug,

(o) and, means formed on said key .means for engaging each of said codepins for displacing each of them axially within their respective bores apredetermined amount sufficient to retract the respective lock pins intotheir respective bore so as to permit relative rotation of the plugmember to open the lock only after the drive means has been engaged,

(p) and means for connecting said key guide for free relative rotationwith respect to said plug member to deter drilling of said lock.

6, A lock construction comprising:

(a) a plug member having a head end portion and a connected stemportion,

(b) said head end portion having a plurality of bores extending axiallytherethrough,

(c) said bores being circumferentially spaced about said head,

(d) a pipe member mounted on the stem of said plug whereby said plugmember may rotate relative to said pipe member,

(e) said pipe member having a plurality of bores formed therein, saidbores being circumferentially spaced so as to be disposed in axialalignment with the bores in said plug,

(f) means for connecting said pipe on said stem in contiguousrelationship to the head end portion, (g)J a lock pin located in eachbore of said pipe mem- (h) spring means normally biasing each of saidlock pins so that the ends of said lock pins normally extend into thealigned bores of said head end portion to normally prohibit relativerotation between said plug and pipe member,

(i) a code pin disposed in each bore of said head end portion,

(j) said code pins being of varying lengths,

(k) a key guide connected to said plug, means for rotatably connectingsaid key guide to said plug,

(l) a lock housing encasing said pipe and plug members,

(m) said housing having an inturned lip covering the axis of the boresof said head end portion, said lip being slightly spaced from the faceof said plug,

(n) a key way formed in the lip of said housing,

(o) a drive means connected to the face of said plug member adjacentsaid inturned lip,

(p) key means for operating said lock,

(q) said key means including a complementary driving means adapted toengage the drive means of said plug member,

(r) and, means formed on said key means for engaging each of said codepins for displacing each of them axially within their respective bores apredetermined yamount sucient to retract the respective lock pins intotheir respective bore a corresponding amount to permit relative rotation-of the plug to open the lock as the key means is turned.

7. A tumbler lock comprising:

(a) a tubular housing having an inturned annular flange to dene thefront facing of said lock,

(b) means defining an internal shoulder formed on the interior of saidhousing intermediate the ends thereof and spaced from the inner surfaceof said llange,

(c) a plug having a head end portion and a connected reduced stemportion rotatably journalled within said housing,

(d) said head end portion being disposed to abut against said internalshoulder of said housing,

(e) an annular pipe member mounted on the stem portion of said plugwhereby said pipe member is disposed contiguous to the head end portionof said plug,

(f) means for securing said pipe member within said housing and xedthereto whereby said plug may rotate relative to said pipe member uponthe actuation of said lock,

(g) said pipe having a plurality of bores circumferentially spacedtherearound,

(h) and said head end portion of said plug having corresponding borescircumferentially spaced therearound disposed in axial alignment withthe bores of said pipe member in the locked position of said lock,

(i) the axis of said bores being disposed behind the flange of saidhousing,

(j) a key guide connected to the head end of saidI plug,

(k) said key guide and flange deiining therebetween an annular space toform a key opening,

(l) a lock pin `disposed in each bore of said pipe member,

(m) means biasing each of said lock pins so that the end portionsthereof normally project into the corresponding aligned bore of saidhead end portion in the normal locked position thereof,

(n) a code pin disposed in each of the bores of said head end portion ofthe plug,

(o) the ends of the respective code pins extending f orwardly of saidhead end portion,

(p) said lock pins and code pins being disposed in axial end-to-endrelationship so that axial displacement of said code pin a predeterminedamount effects retraction of said lock pins against its biasing means acorresponding amount sufcient to effect disengagement of said lock pinsfrom the bore of said head end portion,

(q) a drive means connected to the front of said head end portion ofsaid plug member,

(r) and, a key means operative to engage said code pins and said drivemeans whereby said code pins are axially displaced prior to theengagement of said drive means by said key means so that the drive ofsaid plug member upon the turning of said key means is affected Ionlyafter displacement of said code and lock pins to their respectiveoperative lock turning position has been attained,

(s) and means for rotatably journalling said key guide relative to thehead end portion of said plug member to prohibit the drilling of thesame.

8. The invention as defined in claim 7 wherein said drive means includesa pin projecting forwardly of said head end portion of said plug, andsaid key means includes a plurality of notched out portions on theexternal surface thereof to define seats for receiving driving pin andcode pins.

9. The invention as deiinedV in claim 7 wherein said lock pin includesstop means to limit the axial displacement thereto to prohibitoverstressing said biasing means.

10. The invention as defined in claim 7 and including means forretaining said lock pins within their respective bores to enhancechanging yof the code pins.

1,1. The invention as dened in claim 10 wherein said latter meansincludes -an internal shoulder formed in the bores of said pipe member,and said lock pins each having a complementary flange to abut againstsaid shoulder for retaining said lock pin within its respective bore.

12. The invention as dened in claim 10 wherein said latter meansincludes a counter bore formed in the respective bores of the head endportion to receive the pro` jected ends of said lock pins.

References Cited MARVIN A. CHAMPION, Primary Examiner. EDWARD C. ALLEN,Examiner.

P. TEITELBAUM, Assistant Examiner.

1. A TUMBLER LOCK COMPRISING: A HOUSING, A PAIR OF JUXTAPOSITIONEDRELATIVELY MOVABLE MEMBERS DISPOSED WITHIN SAID HOUSING, EACH OF SAIDMEMBERS HAVING A PLURALITY OF AXIALLY ALIGNED BORES FORMED THEREIN, LOCKPINS MOUNTED IN THE BORE OF ONE OF SAID MEMBERS, MEANS FOR NORMALLYBIASING SAID LOCK PINS SO THAT THE ENDS OF SAID RESPECTIVE LOCK PINSEXTEN INTO THE ALIGNED BORES OF SAID OTHER MEMBER TO PROHIBIT RELATIVEMOVEMENT THEREBETWEEN, CODE PINS DISPOSED IN THE BORE OF SAID OTHERMEMBER, A KEY GUIDE, MEANS FOR CONNECTING SAID KEY GUIDE FOR FREERELATIVE ROTATION WITH RESPECT TO SAID OTHER MEMBER, AND A KEY MEANS FOREFFECTING AXIAL DISPLACEMENT OF SAID CODE PINS AND LOCK PINS APROPORTIONAL AMOUNT TO DISENGAGE SAID LOCK FROM SAID OTHER MEMBER, ANDCOMPLEMENTARY MEANS ON SAID KEY MEANS AND SAID OTHER MEMBER FOREFFECTING A DRIVING CONNECTION BETWEEN SAID KEY MEANS AND SAID OTHERMEMBER WHEREBY SAID DRIVING CONNECTION IS ENGAGED ONLY AFTER SAID CODEPINS HAVE BEEN DISPLACED A PROPORTIONAL AMOUNT NECESSARY TO PERMITRELATIVE MOVEMENT BETWEEN SAID MEMBERS.